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Objectives: There is data scarcity on the overall effects of pneumococcal conjugate vaccines (PCVs) on otitis media (OM) in low- and middle-income countries. The impact of the 13-valent PCV (PCV13) program on OM was evaluated in Cameroon where infant vaccination was implemented in July 2011 using a 3-dose primary series at 6, 10 and 14 weeks of age. Methods: Through community-based surveillance, we used a retrospective cohort study design to assess OM prevalence among PCV13-vaccinated children aged 24 to 36 months in 2015. This was compared with a 2013 age-matched cohort of PCV13-unvaccinated children. OM was diagnosed by clinical inspection for chronic suppurative OM (CSOM) and tympanometry for OM with effusion (OME). CSOM was defined as draining of the middle ear with duration of more than 2 weeks and prolonged OME was defined as a flat 'type B' tympanogram. PCV13-vaccinated and PCV13-unvaccinated cohorts were compared by calculating prevalence odds ratios for OM and baseline characteristics. Results: Altogether, 111 OM cases were identified; 42/433 (9.7%) in the PCV13-unvaccinated in 2013 and 69/413 (16.7%) in the PCV13-vaccinated cohort in 2015. In the 2013 baseline survey, 3/433 (0.7%) children were identified with unilateral CSOM compared to 9/413 (2.2%) in the PCV13-vaccinated cohort in 2015. Bilateral prolonged OME was diagnosed in 7/433 (1.6%) PCV13-unvaccinated children and in 12/413 (2.9%) in PCV13-vaccinated children. Proportions of children with unilateral prolonged OME were 31/433 (7.2%) in the PCV13-unvaccinated group compared with 48/413 (11.6%) in the PCV13-vaccinated group. Multivariate logistic regression analysis showed evidence that PCV13-vaccinated children in 2015 had 40% less risk of contracting OM compared to PCV13-unvaccinated children in 2013 (adjusted prevalence odds ratios = 0.60 [95% confidence interval: 0.38 to 0.94], P = 0.025). Additionally, attributable proportion estimates show that, 58% of OM infections among the PCV13-vaccinated group would still have occurred despite PCV13 vaccination. Conclusion: Our findings provide significant evidence on the effect of PCV13 in decreasing OM or OME among children in this age group. It also supports justification for government's continuation of PCV13 immunization program in the absence of GAVI's funding. Further research is needed to assess the long-term impact of the PCV13 program on in OM Cameroon.
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INTRODUCTION: Measles is one of the most contagious of all infectious diseases, for example, up to 9 out of 10 susceptible people with close contact to a measles patient will develop measles. In countries where measles is rare, transmissions in health care facilities have been a key factor in amplifying outbreaks OBJECTIVES: Describe the hospital transmission of measles among unvaccinated children in pediatric service, challenges faced and recommendations for health care settings by applying the Swiss cheese model. METHOD: Between December 2019 and January 2020; multiple exposures to measles cases occurred. The incident and factors that led to the outbreak are described. The matrix and fusion genes, non-coding region sequence analysis was also conducted on the 3 strains isolated from the cases. RESULTS: The outbreak extended from December 2019 to January 2020, which resulted in 110 exposed individuals (85 health care workers and 25 patients). Eleven (44%) children exposed were vaccinated, 14 (56%) were not yet vaccinated, and the measles status of 10 (11.8%) HCWs was not known at the time of the outbreak. Two infants acquired measles in the hospital, and both required ICU care. Three infants and one HCW received immunoglobulin. The phylogenetic tree of the matrix and fusion genes, non-coding region sequencing confirmed that all three cases had 100% identical measles strain. CONCLUSIONS: In countries where measles elimination goals are achieved, a multifaceted approach to prevent measles transmission in health care is vital to maintain patient safety.